Work machines, for example articulated dump trucks, have several axles that can heat up during operation from braking and other heat generating tasks. Axle oil flows through the axles to lubricate and cool the axle components. The axle oil has a preferred operating temperature range for most effective use. Excessive heating of the axle oil as well as excessive cooling of the axle oil can be detrimental to the axle oil, as well as to bearings, seals and other axle components. During testing, it was also found that while operating at cold temperatures (for example 25° C.), vacuum levels on the axle suction lines can exceed supplier recommendations.
Typically an axle cooling system will run at all times while the engine is running because the pump that drives the axle cooling system is driven off the engine. This results in constant fuel burn with an added load on the engine, and can cause unnecessary cooling of the axles when the axle oil is not up to the preferred operating temperature range.
It would be desirable to have an axle cooling system that could be activated and deactivated depending on the axle oil temperature.